Recently, the expression of acetylcholinesterase1 (AChE1) in honeybee worker has been found to be seasonally fluctuated. Seasonal investigation on the AChE1 expression profiles revealed that it is abundantly expressed in January but its expression was completely abolished in February in both head and abdomen. In an attempt to predict the physiological function of seasonally expressed AChE1, proteomic analysis of honeybee worker was conducted using the samples collected in January and February. Total protein samples separately extracted from the head and abdomen of honeybee forager were compared by 2-D electrophoresis (2-DE). More than 2-fold differences in expression patterns between the two different samples were observed in 50 and 85 protein spots in the head and abdomen, respectively. Among them, 20 protein spots showing >17-fold differences in expression between the two different samples of the head were identified by mass spectrometry. Most of the proteins were identified to be the major royal jelly protein (MRJP) families (e.g., MRJP, MRJP2 and MRJP3), which are known to be expressed in nurse bees during brooding season, and their expression was significantly higher in January than in February. This result was unexpected because brooding usually began in the study site apiary during February and the worker bees used for analysis were assumed to be foragers (old workers). Thus, current findings suggest, though speculative, that the workers collected in January may function as nurses despite their old ages in January or that MRJPs may have other not-yet-characterized functions, which is apart from the conventionally known roles. Finally, possible association of MRJPs with AChE1 was discussed.

Cadmium (Cd) pollution is thought to be one of the leading threat to the environment due to its high toxicity. However, the molecular responses induced by Cd have so far been grossly overlooked. This study examines the morpho-physiological alterations combined with proteome changes in leaves of Sorghum bicolor when exposed to Cd. Ten days old sorghum seedlings were exposed to different concentrations (0, 100, and 150 μM) of CdCl2 and a significant accumulation of Cd in the leaves was recorded by ICP analysis. Furthermore, the effects of Cd exposure on protein expression patterns in S. Bicolor was investigated by two-dimensional gel electrophoresis (2-DE) and the 2-DE profile of leaf proteins from both control and Cd-treated seedlings were compared quantitatively using Progenesis SameSpot software. Results lined to morphological changes that plants treated with Cd suffered reduction of growth. The concentration of Cd was markedly reversed by the Cd treatments, whereas the absorption degree of Cd was increased by the higher concentration of Cd by confocal microscopy. Using 2-DE method, a total of 33 differentially expressed protein spots were identified by MALDI-TOF-TOF mass spectrometry. Of those, 13 protein spots were significantly enhanced/reduced while 20 reduced under Cd treatment. The most of the up-regulated proteins are involved in oxidative response, glutathione and sulfur metabolism as well as the secondary metabolite biosynthesis. Collectively, our study provides insights into the integrated molecular mechanisms of early responses to Cd and growth and physiological characteristics of sorghum seedlings hoping to provide references on the mechanism of heavy metal damaging plants.

Sub-cellular proteomics provide insight into the molecular mechanisms of plant cell modulation of protein accumulation in intracellular compartments regarding various perturbations, and thus provides rectified knowledge about signal transduction in organelles. Mitochondria are important organelles for cellular respiration within the eukaryotic cell and serve many important functions including vitamin synthesis, amino acid metabolism and photorespiration for the cell as well. To define the mitochondrial proteome of the roots of wheat seedling, a systematical and targeting analysis were carried out on the mitochondrial proteome from 15 days-old wheat seedling roots material. Mitochondria were isolated by Percoll gradient centrifugation; and extracted proteins were separated and analyzed using Tricine SDS-PAGE along with LTQ-FTICR mass spectrometry. From the isolated mitochondrial proteins, a total of 140 proteins were identified. The identified proteins were functionally classified into 12 classes using ProtFun 2.2 server based on cellular roles, Proteins were shown to be involved in including amino acid biosynthesis (17.1%), biosynthesis of cofactors (6.4%), cell envelope (11.4%), central intermediary metabolism (10%), energy metabolism (20%), fatty acid metabolism (0.7%), purines and pyrimidines (5.7%), regulatory functions (0.7%), replication and transcription (1.4%), translation (22.1%), transport and binding (1.4%), and unknown (2.8%). These results indicated that many of the protein components present and functions of identified proteins are common to other profiles of mitochondrial proteomes performed to date. The data presented here will begin to reveal a better understanding the characteristics of proteins and metabolic activity in mitochondria in wheat roots.

Grain sorghum (Sorghum bicolor) is a major staple for a large portion of the world. The crop ranks fifth among the cereals world-wide with respect to its importance for food and feed applications. To this end, the grain harvested from sorghum, and the millets provides an important source for dietary calories and protein for approximately one billion people in the semi-arid regions of the world. However, grain sorghum products are known to have relatively poor digestibility, only approximately 50%–70%, in comparison with other grains, such as wheat and maize, which tend to have digestibility percentages over 80% and 70%, respectively. Protein with high digestibility is by definition nutritionally superior owing to the increased availability of amino acids. Digestibility can be impacted by both protein–protein and⁄or protein–nonprotein interactions. However, with respect to grain sorghum, it is thought that the major factor influencing digestibility is the former because of high protein cross-linking around the protein body. To understand the mechanism of seed storage proteins in the sorghum, the proteomic analysis was carried out between the wild(BTX623) and mutant(M271207) genotypes of sorghum. Proteins were separated from the mature seed using IEF in the first-dimension and SDS-PAGE in the second dimension along with hybrid LTQ-FTICR mass spectrometry. After image analysis using Progenesis SameSpot software, we identified the 62 differential expressed protein spots out of 293 protein spots. Out of total differential expressed spots, 35 differential expressed protein spots (more than2-fold) were analyzed by mass spectrometry. Out of 35 protein spots, we were identified 20 protein spots as up-regulated and 15 protein spots as downregulated, significantly. In our proteomic investigation, the candidate proteins may provide novel clues for better understanding the characteristics of seed proteins in Sorghum.

Chilling stress affects growth and yield of warm-climate crops such as soybean (Glycine max L.) that is susceptible to low temperature (10-18℃). A comparative proteomic approach was employed to explore the mechanisms underlying soybean response to chilling stress. Soybean seedlings were germinated for 3-4 days and exposed to low temperature (10℃) for 3 days, and the proteins were extracted from seedling leaves. Protein separation by SDS-PAGE followed by liquid chromatography electro-spray ionization tandem mass spectrometry (LC-ESI MS/MS) was effective approach to identify proteins, based on the number of peptides reliably identified. A total of 77 proteins out of 704 proteins were identified in the presence of chilling stress. Most proteins identified had functions related to cell signaling, metabolism, energy and transport, protein biosynthesis and degradation, cytoskeleton, and were involved in regulating reactions and defending against stress. It is therefore likely that the response of soybean plant’s proteome to chilling stress is complex, and that the identification proteins may play an important role in regulating adaptation activities following challenge to chilling stress to facilitate cellular homeostasis. Furthermore, our result suggest that new ways of engineering stress-tolerant plants responding climate change by providing outline for agriculturally important chilling stress.

Although it is known that the composition of high-molecular weight glutenin subunits (HMW-GSs) and low-molecular weight glutenin subunits (LMW-GSs) are important factor for bread, noodle and cookie, it is still not clear which HMW-GSs and LMW-GSs confer improved processing properties and how those HMW-GSs and LMW-GSs interact each other. In this study, to investigate distinctive glutenin proteins for characteristic processing properties for noodle, glutenins extracted from seeds of several Korean and Chinese wheat cultivars were focused in IPG gel strip and subjected to SDS-polyacrylamide gel electrophoresis. Differential protein expression level was analyzed using image master platinum 6. Then to characterize the HMW-GSs of Korean cultivar Uri, extracted glutenin proteins were separated by two dimensional gel electrophoresis. Nine spots digested with trypsin resulting peptide fragmentation were identified by LC ESI-MS/MS and MASCOT database. We also separated HMW-GSs from wheat cultivar Uri by fast protein liquid chromatography (FPLC) withResource Phe column using gradient buffer condition with 4M Urea and 0.45M ammonium sulfate.Each single band of 1Dx 2.2, 1Bx7 and double bands of 1Dy8 and 1By12 were separated.

Wheat-rye translocation lines were developed to produce a main crop resistant to biological and physical stress. 'Chaupon' rye contains 2RL chromatin to harbor resistance genes for powdery mildew and leaf rust. In order to identify chromosome 2RL-derived rye proteins and 2RL-perturbed proteins in wheat-rye translocation lines, the gel-based proteomics was employed with 'Coker797' (non-2RL), 'Hamlet' (2RL) and 'near-isogenic line' (stabilized 2RL). The leaf proteome was resolved on 2D-gel, resulting in 216 spots in a final selection. A total of 90 proteins were identified with the identification success rate of 42%. The identified proteins were classified by functional annotation: metabolism (64%), cellular process (5%), translation (2%), regulatory function (1%) and hypothetical (28%). The proteins belonged to metabolism were subdivided into carbohydrate metabolism (36%), energy metabolism (35%), metabolism of lipid, amino acid, other amino acid and biosynthesis of secondary metabolites (each 6%) and others (5%). A total of 53 proteins were differentially expressed, in which β-glucosidase, in particular, originated from the chromosome 2RL of rye, was exclusively appeared in NIL. In addition, small Ras-related GTP binding-protein assigned to wheat was predominantly found in 2RL rye chromatin-possessing NIL. These results suggest that the acquired genetic traits obtained from rye 2RL enhance the resistance to biotic and abiotic stress in wheat-rye translocation lines by altered the proteome expression. In leaf metabolome analysis, 11 predominant metabolites containing trans-aconitate, glutamate, and betaine were identified by 1H-NMR-based metabolite fingerprinting. The overall metabolites pattern of NIH appears to be closer to Coker797 rather than Hamlet. Thus, the metabolic phenotype of NIL was not so much lineated from Hamlet contrast to proteomic phenotyping.

Rice with purple colored pericarp deposit anthocyanin on the seed coat and color accumulation increased rapidly during seed development. The purple color of rice pericarp is genetically determined by the Prp locus. Inheritance of purple pericarp was studied in Prp/ Kumgangbyeo (indica type Korean variety). Pericarp color of the F1 plants was purple and the F2 population of 274 plants segregated into 3 purple: 1 white ratio indicating dominant nature of the purple color. Comparative proteomic approaches using 2-DE were applied to analyze the protein profiles and molecular mechanism of purple color formation in ricepericarp. Results revealed that approximately 1,500protein spots were reproducibly detected in the gels with silver staining across the two biological replicates. Among them, 46 proteins were expressed differentially between purple color pericarp rice and white color pericarp of the wild type rice, in which 28 and 16 protein spots were more than two fold up regulated in the wild type and purple pericarp, respectively. MALDI-TOF MS analysis of nine spots revealed that putative fructokinase,embryo-specific protein and one unknown proteins were abundant in the wild type, whereas, anthocyanidin synthase, putative chloroplast inner envelope protein, and dihydroflavonol reductase were highly abundant in the Prp rice. Results indicated anthocyanidin synthase and/or dihydroflavonol reductase might be involved in the biosynthetic pathway of the purple color formation in the rice pericarp. [This research was supported by the Grant funded by Agricultural R&D Promotion Center, ARPC (IPET project number: 108091-05-1-CG000)].

To better understanding the function of the luminal sub-organelles within the thylakoid network, we have carried out a systematical analysis and identification of the lumenal proteins in the thylakoid of wheat by using Tricine / 1D-PAGE, and LTQ-ESI-FTICR mass spectrometry followed by SWISS-PROT database searching. We isolation and fractionation these membrane from fully developed wheat leaves using a combination of differential and gradient centrifugation couple to high speed ultra-centrifuge. After collecting all proteins to eliminate possible same proteins, we estimated that there are 407 different proteins including chloroplast, chloroplast stroma, lumenal, and thylakoid membrane proteins excluding 20 proteins, which were identified in nucleus, cytoplasm and mitochondria. A combination of these three programs (PSORT, TargetP, and TMHMM) was found to provide a useful tool for evaluating chloroplast localization, transit peptide, transmembranes, and also could reveal possible alternative processing sites and dual targeting. Finally, we report also sub-cellular location specific protein interaction network using Cytoscape software, which provides further insight into the biochemical pathways of photosynthesis. The present work helps understanding photosynthesis process in wheat at the molecular level and provides a new overview of the biochemical machinery of the thylakoid in wheat.

Photoperiod sensitive genetic male sterile (PGMS) rice is sterile mutant controlled by photoperiod. A PGMS mutant 920S was sterile grown under long-day (LD) photoperiod (14 h light/10 h dark) but fertile grown under short-day (SD) photoperiod (10 h light/14 h dark). Proteome analysis revealed that 12 protein spots were differentially expressed in the spikelets of 920S plants either treated with LD or SD photoperiod. Among these proteins, three proteins including chlorophyll a/b binding protein, vacuolar ATPase β-subunit,~;α-tubulin and an unknown protein were more than three-fold abundant in the spikelet of the SD-treated plants than those of the LD-treated plants. On the other hand, eight proteins including acetyl transferase, 2, 3- biphosphoglycerate, aminopeptidase N, pyruvate decarboxylase, 60S acidic ribosomal protein and three unknown protein spots were more abundant in the spikelets of the LD-treated plants than those of the SD-treated plants. The results suggest that the observed proteins may be involved in sterile or fertile pollen development under LD or SD photoperiod respectively in the PGMS mutant rice.

Spikelet proteins expressed at the young microspore stage in rice were separated and analysed by two-dimensional polyacrylamide gel electrophoresis (2DE). The separated proteins were electro blotted onto a polyvinylidene difluoride (PVDF) membrane, and 50 proteins were analyzed by a gas-phase protein sequencer. The N-terminal amino acid sequences of 20 out of 50 proteins were determined. N-terminal regions of the remaining proteins could not be sequenced because of blocking. The internal amino acid sequences of proteins were determined by sequence analysis of peptides obtained by the Cleveland peptide mapping method. Results revealed the presence of the photosynthetic apparatus at rice young microspore stage. Major proteins identified in this study could be used as a marker for various studies on physiological stresses.